If you feel that a 6-speed is unnecessary, Richmond also offers a 5-speed setup that may be more to your liking. According to Terry Meehan at Sport Center in Hoboken, NJ, can be installed with little difficulty. Tony elaborated on an installation in a 1981 Corvette, but informed us that just about any Vette with a 4-speed can be easily updated to this overdrive unit with little difficulty.
The Richmond 5-speed practically slides right in, as it uses the same bellhousing bolt pattern at the original 4-speed, and the original shifter from the 4-speed can be reused as well. As long as you get the proper input shaft dimensions, there is no need for any gearbox or bellhousing modifications. However, there are two points that need to be addressed: The driveshaft yoke going into the gearbox needs to be the larger unit as used in the 6-speed, and the rear crossmember requires a small flange welded to it to accomodate the 5-speed's rear mount.
Many of you have written to Vette to learn more about the feasability of installing a fourth-generation Camaro or Firebird T56 6-speed gearbox in your Corvette. Although the OEM T56 has many outstanding feature, including an internal rail shift mechanism, small size and relatively light weight, this gearbox may seem an easy sawp, but in truth, it's quite difficult to make it's installation a bolt-in affair.
Despite the fact that it will bolt onto the back of any small- or big-block V8 engine, production units for General Motors applications utilize a pull-style clutch, as employed on all 1993-98 Camaros and Firebirds. Because of this, the T56 bellhousing must be used. If you look at how the geometry of thearm works,you can see how it changes the motion of the slave cylinder to activate a pull-style clutch. The slave cylinder must be checked for actual bolt-on compatibility; if not, a T56 slave cylinder is needed. Since the T56 has the slave cylider mounted on the driver's side, C4 Corvettes don't pose a serious threat ti its' installation, because a flexible hose is easier to move than a fixed linkage. On 1982 and older Corvettes, getting the Z-bar linkage to work would either require a major redesign of the linkage system or a conversion to a hydraulic system. There are other teething problems to be taken care of, amking the expense of the T-56 conversion questionable.
When we called Borg-Warner to see if it offers a T-56 conversion package for Corvette owners, they told us that, unfortunately, no such conversion currently exists. (1998) A knowledgable technican from one of their distributors in the Northeast was versed in the sawp, and she explained that aside from a major clutch re-engineering, many additional modifications would be required to make the T56 work.